Spin Hall photoconductance in a 3D topological insulator at room temperature

Abstract

Three-dimensional topological insulators are a class of Dirac materials, wherein strong spin-orbit coupling leads to two-dimensional surface states. The latter feature spin-momentum locking, i.e., each momentum vector is associated with a spin locked perpendicularly to it in the surface plane. While the principal spin generation capability of topological insulators is well established, comparatively little is known about the interaction of the spins with external stimuli like polarized light. We observe a helical, bias-dependent photoconductance at the lateral edges of topological Bi2Te2Se platelets for perpendicular incidence of light. The same edges exhibit also a finite bias-dependent Kerr angle, indicative of spin accumulation induced by a transversal spin Hall effect in the bulk states of the Bi2Te2Se platelets. A symmetry analysis shows that the helical photoconductance is distinct to common longitudinal photoconductance and photocurrent phenomena, but consistent with the accumulated spins being transported in the side facets of the platelets. Our findings demonstrate that spin effects in the facets of 3D topological insulators can be addressed and read-out in optoelectronic devices even at room temperatures.

References in corpus (34)

• Topological Insulators
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Topological Insulator Materials
• Observation of Floquet-Bloch states on the surface of a topological insulator
• First direct observation of Spin-textures in Topological Insulators : Spin-resolved ARPES as a probe of topological quantum spin Hall effect and Berry's phase
• Dirac materials
• Control over topological insulator photocurrents with light polarization
• Ultrafast Optical Excitation of a Persistent Surface-State Population in the Topological Insulator Bi2Se3
• Measurement of intrinsic Dirac fermion cooling on the surface of a topological insulator Bi${}_2$Se${}_3$ using time- and angle-resolved photoemission spectroscopy
• Optical characterization of topological insulator surface states: Berry curvature-dependent response
• Ultrafast photocurrents at the surface of the three-dimensional topological insulator ${\mathrm{Bi}}_2{\mathrm{Se}}_3$
• Current-Induced Polarization and the Spin Hall Effect at Room Temperature
• Topological Surface States and Dirac point tuning in ternary Bi2Te2Se class of topological insulators
• Observation of inverse spin Hall effect in bismuth selenide
• Photo-thermoelectric and photoelectric contributions to light detection in metal-graphene-metal photodetectors
• Ultrafast helicity control of surface currents in topological insulators with near-unity fidelity
• Electrical detection of the spin polarization due to charge flow in the surface state of the topological insulator Bi_1.5 Sb_0.5 Te_1.7 Se_1.3
• Room temperature high frequency transport of Dirac fermions in epitaxially grown Sb_2Te_3 based topological insulators
• Generating Spin Currents in Semiconductors with the Spin Hall Effect
• Electrical injection and detection of spin-polarized currents in topological insulator Bi2Te2Se
• Enhanced photogalvanic current in topological insulators via Fermi energy tuning
• Gigantic surface life-time of an intrinsic topological insulator revealed via time-resolved (pump-probe) ARPES
• Driven Electronic States at the Surface of a Topological Insulator
• Generation of Transient Photocurrents in the Topological Surface State of Sb${}_2$Te${}_3$ by Direct Optical Excitation with Mid-Infrared Pulses
• Ultrafast spin polarization control of Dirac fermions in topological insulators
• Photogalvanic probing of helical edge channels in 2D HgTe topological insulators
• Defect induced negative magnetoresistance and surface state immunity in topological insulator BiSbTeSe2
• Persistent Optical Gating of a Topological Insulator
• Anisotropic photoconductivity in graphene
• Opto-Electronic Characterization of Three Dimensional Topological Insulators
• Helicity dependent photovoltaic effect in Bi2Se3 under normal incident light
• Local photocurrent generation in thin films of the topological insulator Bi2Se3
• Tunable photo-galvanic effect on topological insulator surfaces via proximity interactions
• Strongly anisotropic spin-orbit splitting in a two-dimensional electron gas

Cited by in corpus (10)

• Direct visualization of current induced spin accumulation in topological insulators
• Photocurrent as a multi-physics diagnostic of quantum materials
• Infrared/Terahertz Spectra of the Photogalvanic Effect in (Bi,Sb)Te based Three Dimensional Topological Insulators
• Intrinsic spin Hall effect in topological insulators: A first-principles study
• Emerging spintronics phenomena and applications
• Photo-induced anomalous Hall effect in the type-II Weyl-semimetal WTe2 at room-temperature
• Switchable quantized conductance in topological insulators revealed by the Shockley-Ramo theorem
• THz Photodetector using sideband-modulated transport through surface states of a 3D Topological Insulator
• Inverse Spin Hall Effect Induced by Asymmetric Illumination of Light on Topological Insulator Bi${}_2$Se${}_3$
• Terahertz electro-optic effect in Bi${}_2$Se${}_3$ crystals